Editing Bracken (section)

=== In animals ===
Ptaquiloside from bracken has been shown to be [[carcinogen]]ic in some animals.<ref name=Evans71>{{cite journal |vauthors=Evans IA, Widdop B, Jones RS |title=The possible human hazard of the naturally occurring bracken carcinogen |journal=Biochem. J. |volume=124 |issue=2 |pages=29P–30P |date=September 1971 |pmid=5158492 |pmc=1177200 |display-authors=etal|doi=10.1042/bj1240029pa }}</ref> Animals may ingest the plant when other sources of food are unavailable, such as during droughts or after snowfalls.

In cattle, bracken poisoning can occur in acute and chronic forms, acute poisoning being the most common. Milk from cows that have eaten bracken may also contain ptaquiloside, which is especially concentrated in [[buttermilk]].<ref name="rasmussen"/> In pigs and horses, bracken poisoning induces vitamin B1 deficiency.<ref>{{cite book |author1=Auld, RA |author2=Medd, RW |title=Weeds |publisher=Inkata Press |location=Sydney |year=1992 }}</ref>